Coffee futures staged a strong start to September, attempting in New York to record their second highest close in more than a year, as data showing a slump in world exports crystallised concerns of tighter supplies.

Arabica coffee futures for December stood up 3.8% at 153.65 cents a pound in late deals in New York, a level which, if held to the close, would represent the strong finish for the contract, bar one, since May last year.

'Bullish as anything'

The gains were attributed in part to technical factors, with daily and, in particular weekly, charts on arabica deemed supportive to price.

"The weekly chart is bullish as anything. It is something to get excited about," Jack Scoville, at US broker Price Futures, told Agrimoney.com.

He also flagged talk of growing talk that a series of frosts in Brazil had wrought more damage on trees than originally thought - boding ill for prospects for a 2017 harvest which was already expected in arabicas to fall below this year's, given the country's cycle of alternate higher and lower producing years.

Most producers in major arabica-growing areas "talk of losses and that trade estimates are overstated", Mr Scoville said, adding that while "the industry has estimated the crop as high as 55m bags, but there are many doubters about this estimate.

"Some now talk of production for all of Brazil well below 50m bags," he said, noting talk of some plantations suffering notable frost damage.